JP4577227B2 - Vehicle power generation control device - Google Patents

Description

  The present invention relates to a vehicular power generation control device that controls a power generation state of a vehicular generator.

  In recent years, the temperature in the engine room has risen, and improvement in heat resistance of a vehicular generator has been demanded. In particular, a power generation control method for a vehicle generator that suppresses the temperature rise of these components in a high-temperature use environment is required for a vehicle power generation control device in which the temperature of the rectifier, the stator winding, and the bearing is high.

As a conventional technique for suppressing such a temperature rise, when the temperature of the vehicle power generation control device exceeds a predetermined value, the excitation current value is suppressed to reduce the power generation amount of the vehicle generator, thereby reducing the component temperature. A control method to suppress is known (for example, refer to Patent Documents 1 and 2).
JP-A-60-51421 (page 2-3, FIG. 1-4) Japanese Unexamined Patent Publication No. 4-229100 (page 3-6, FIG. 1-6)

  By the way, in the control method disclosed in Patent Document 1, in the environment of the rotational speed of the vehicular generator and the ambient temperature of the vehicular generator that changes according to the running state of the vehicle, There has been a problem that the temperature difference with the temperature of the vehicle power generation control device changes, the temperature cannot be accurately controlled, and power generation may be excessively suppressed. In particular, in urban areas, since temperature changes are frequently repeated, there is concern about deterioration of the charge / discharge balance and voltage fluctuation due to excessive power generation suppression, and a control method that minimizes these adverse effects is demanded.

  The present invention has been created in view of such a point, and an object thereof is to provide a vehicle power generation control device capable of preventing excessive power generation suppression.

In order to solve the above-described problem, the vehicle power generation control device of the present invention includes a temperature detection unit that detects a temperature of a predetermined measurement location, and a temperature detected by the temperature detection unit exceeds a predetermined value. A suppression value that is variable at a predetermined change rate is determined, and based on this suppression value, power generation suppression means that suppresses the amount of power generated by the vehicle generator, and excitation current supply to the excitation winding of the vehicle generator is stopped. The power generation suppression means is configured so that the power generation voltage does not exceed a value obtained by subtracting the suppression value from an adjustment voltage setting value for setting the power generation voltage of the vehicle generator and / or excitation. the value obtained by subtracting the suppression value from the excitation current limit value so that the excitation current does not exceed the set upper limit of the excitation current supplied to the winding, varying the power generation amount by increasing or decreasing the excitation duty for turning on and off the switching elements It is made to. By performing power generation suppression that reduces the power generation amount at a predetermined change rate when the detected temperature exceeds a predetermined value, it is possible to prevent excessive power generation suppression due to an instantaneous temperature rise. Further, by changing the adjustment voltage set value and the excitation current limit value, the amount of power generation can be easily or reliably increased or decreased.

  Further, the power generation suppression means described above stops the power generation amount suppression of the vehicular generator when the temperature detected by the temperature detection means falls below a predetermined value after suppressing the power generation amount, and at a predetermined change speed. It is desirable to increase the amount of power generation. As a result, it is possible to prevent the amount of power generation from rapidly increasing when the temperature returns to the normal range, and thus it is possible to stabilize engine rotation by suppressing a rapid increase in power generation torque.

Moreover, it is desirable that the power generation suppression unit described above sets the speed change amount for suppressing the power generation amount according to the difference between the temperature detected by the temperature detection unit and a predetermined value.

  In addition, it is desirable that the power generation suppression unit described above sets the speed change amount for suppressing the power generation amount so as to be proportional to the difference value between the temperature detected by the temperature detection unit and the predetermined value. Thereby, the amount of power generation suppression can be changed according to the degree of temperature rise, and the component temperature of the vehicular generator can be quickly lowered.

  Hereinafter, a power generation system including a vehicle power generation control device according to an embodiment to which the present invention is applied will be described with reference to the drawings.

[ Reference embodiment]
FIG. 1 is a diagram showing a configuration of a vehicle generator in which a vehicle power generation control device of a reference embodiment is built, and also shows a connection state between the vehicle generator and a battery or an electric load. .

  As shown in FIG. 1, the vehicular generator 1 according to the present embodiment includes an excitation winding 21, a stator winding 22, a rectifier 23, and a vehicular power generation control device 2. The vehicle generator 1 is driven by an engine via a belt and a pulley. The exciting winding 21 is energized to generate a magnetic field. The excitation winding 21 is wound around a field pole (not shown) to form a rotor. The stator winding 22 is a multiphase winding (for example, a three-phase winding), and is wound around a stator core to constitute a stator. The stator winding 22 generates an electromotive force due to a change in the magnetic field generated by the excitation winding 21. An AC output induced in the stator winding 22 is supplied to the rectifier 23. The rectifier 23 performs full-wave rectification on the AC output of the stator winding 22. The output of the rectifier 23 is taken out as the output of the vehicle generator 1 and supplied to the battery 3 and the electric load 4. The output (power generation amount) of the vehicle generator 1 changes according to the number of rotations of the rotor and the energization amount of the excitation current flowing in the excitation winding 21, and the excitation current is controlled by the vehicle power generation control device 2. .

  Next, details of the vehicle power generation control device 2 will be described. The vehicle power generation control device 2 includes an excitation drive transistor 11, a freewheeling diode 12, a power generation voltage detection circuit 13, an F duty detection circuit 14, a power generation control circuit 15, and a temperature detection circuit 16.

  The excitation drive transistor 11 is composed of a MOS-FET whose gate is connected to the power generation control circuit 15, whose drain is connected to the output terminal (B terminal) of the vehicle generator 1 via the freewheeling diode 12, and whose source is grounded. It is a switching element. The drain of the excitation drive transistor 11 is connected to the excitation winding 21 via the F terminal. When the excitation drive transistor 11 is turned on, an excitation current flows through the excitation winding 21. Stopped. The freewheeling diode 12 is connected in parallel with the exciting winding 21 and recirculates the exciting current flowing through the exciting winding 21 when the exciting drive transistor 11 is turned off. The generated voltage detection circuit 13 detects the output voltage (generated voltage) of the vehicle generator 1 that appears at the B terminal. The F duty detection circuit 14 detects the excitation duty (F duty) of the excitation drive transistor 11, that is, the ratio of the period during which the excitation drive transistor 11 that is on / off controlled is turned on (on duty ratio). This detection is performed by monitoring the voltage at the F terminal to which the excitation drive transistor 11 is connected. The power generation control circuit 15 performs on / off control of the excitation drive transistor 11 and performs power generation amount suppression control based on the temperature detection result by the temperature detection circuit 16. The temperature detection circuit 16 detects the temperature at a predetermined measurement location of the vehicle power generation control device 2. For example, a temperature detection sensor is attached to the measurement location, and temperature detection is performed based on the sensor output (output voltage or output current). Note that the measurement location where temperature detection is performed does not necessarily have to be a specific location of the vehicle power generation control device 2, and may be another component (for example, in the vicinity of the rectifier 23 or the stator winding 22). A sensor for temperature detection may be attached in the vicinity of a specific part for which temperature reduction is desired in accordance with power generation suppression.

  FIG. 2 is a diagram illustrating a detailed configuration of the power generation control circuit 15. As shown in FIG. 2, the power generation control circuit 15 includes a temperature deviation detection circuit 51, a U / D counter 52, a suppression limit value setting circuit 53, a digital-analog converter (D / A) 54, a selector 55, and an F duty limit. A reference value setting circuit 56, a subtractor 57, voltage comparators 58 and 60, an adjustment voltage reference value setting circuit 59, and a PWM circuit 61 are provided.

  The temperature deviation detection circuit 51 detects and outputs the difference (deviation amount) between the temperature of the vehicle power generation control device 2 itself detected by the temperature detection circuit 16 and a predetermined temperature (predetermined value). The U / D counter 52 performs a speed up / down count operation in accordance with the deviation amount output from the temperature deviation detection circuit 51. The output count value corresponds to the power generation amount suppression value. For example, assuming that a value obtained by subtracting a predetermined temperature from the temperature detected by the temperature detection circuit 16 is a deviation amount, if the deviation amount is positive, that is, if the detected temperature is higher than the predetermined temperature, the U / D counter 52 Up-counting is performed at a speed proportional to the absolute value of the deviation amount. On the contrary, when the deviation amount is negative, that is, when the detected temperature is lower than the predetermined temperature, the U / D counter 52 performs a down-count operation at a speed proportional to the absolute value of the deviation amount. The speed of the count operation corresponding to the deviation amount is determined in advance in consideration of the relative relationship between the temperature of the vehicle power generation control device 2 and the temperature of the rectifier 23 and the like. Further, the deviation amount is negative immediately after the start of power generation, and the count value of the U / D counter 52 is fixed to zero. Thereafter, when the deviation amount becomes positive, the count operation by the U / D counter 52 is started.

  The digital-analog converter 54 generates a voltage value corresponding to the count value of the U / D counter 52. The selector 55 selects and outputs the smaller one of the output value of the digital-analog converter 54 and the output value of the suppression limit value setting circuit 53. The suppression limit value setting circuit 53 sets a suppression limit value for suppressing the power generation amount. If the detected temperature continues to be higher, the count value of the U / D counter 52 continues to increase. Therefore, it is assumed that the power generation amount suppression value continues to increase and the power generation amount becomes zero. Although it is desirable that the amount of power generation is small in order to reduce the temperature, it is desirable to secure a certain amount of power generation from the viewpoint of the power balance. Therefore, in the present embodiment, the suppression limit value of the power generation amount is set by the suppression limit value setting circuit 53 in order to achieve both of them. When the count value of the U / D counter 52 exceeds a value corresponding to the suppression limit value (a value obtained by converting the count value into a voltage value is compared with the suppression limit value), the selector 55 causes the suppression limit value to be compared. Therefore, the power generation amount is not suppressed beyond the suppression limit value.

  The F duty limit reference value setting circuit 56 sets the upper limit value of the excitation duty of the excitation drive transistor 11 as the F duty limit reference value. The subtractor 57 outputs a value obtained by subtracting the output value (the power generation amount suppression value) of the selector 55 from the output value of the F duty limit reference value setting circuit 56 (F duty limit reference value) as the F duty limit value. The voltage comparator 58 is high when the output value of the subtractor 57 is input to the plus input terminal and the output value of the F duty detection circuit 14 is input to the minus input terminal, and the output value of the subtractor 57 is larger. A level signal is output. Conversely, when the output value of the F duty detection circuit 14 is larger, a low level signal is output.

  The adjustment voltage reference value setting circuit 59 outputs a voltage corresponding to the adjustment voltage reference value of the vehicle generator 1. For example, when a voltage obtained by dividing the output voltage of the vehicular generator 1 by the voltage dividing circuit is detected by the generated voltage detecting circuit 13, a voltage value obtained by multiplying the adjustment voltage reference value by the voltage dividing ratio of the voltage dividing circuit is obtained. Output from the adjustment voltage reference value setting circuit 59. In the voltage comparator 60, the output value of the adjustment voltage reference value setting circuit 59 is input to the plus input terminal, and the output value of the generated voltage detection circuit 13 is input to the minus input terminal, and the generated voltage is higher than the adjustment voltage reference value. When it is low, a high level signal is output, and when the generated voltage is higher than the adjustment voltage reference value, a low level signal is output.

  The PWM circuit 61 outputs a PWM (pulse width modulation) signal having a predetermined duty ratio. When both output signals of the two voltage comparators 58 and 60 are at a high level, the duty ratio of the PWM signal is increased. The duty ratio of the PWM signal is decreased when at least one of the output signals of the two voltage comparators 58 and 60 is at a low level.

  The vehicle power generation control device 1 of the present embodiment has such a configuration, and the operation thereof will be described next. As described above, when the temperature detected by the temperature detection circuit 16 exceeds a predetermined temperature, the count value of the U / D counter 52 increases at a speed corresponding to the deviation amount (temperature difference). Therefore, the output value of the digital-analog converter 54 obtained by converting the count value of the U / D counter 52 into a voltage value increases and is subtracted from the F duty limit reference value output from the F duty limit reference value setting circuit 56. The power generation amount suppression value increases. When the state where the detected temperature is higher than the predetermined temperature is maintained, the suppression value of the power generation amount is increased until the suppression limit value set by the suppression limit value setting circuit 53 is reached. Further, the speed until reaching the suppression limit value increases as the deviation amount, which is the difference between the detected temperature and the predetermined temperature, increases. The F duty limit value output from the subtractor 57 gradually decreases with the setting operation of the power generation amount suppression value. When the gradually decreasing F duty limit value becomes smaller than the excitation duty of the excitation drive transistor 11 detected by the F duty detection circuit 14, the output of the voltage comparator 58 changes from high level to low level. Regardless of the output voltage level of the voltage comparator 60, the duty ratio of the output PWM signal is reduced. As a result, the excitation current flowing through the excitation winding 21 is reduced, and the amount of power generation is suppressed.

  Thus, in this embodiment, excessive power generation suppression is performed due to an instantaneous temperature rise by performing power generation suppression that reduces the power generation amount at a predetermined change rate when the detected temperature exceeds the predetermined temperature. Can be prevented. Also, when the detected temperature falls below the specified temperature, the suppression of power generation is stopped, but since the power generation is increased at a predetermined rate of change, power generation is abrupt when the temperature returns to the normal range. It is possible to prevent the amount from increasing, and it is possible to stabilize engine rotation by suppressing a rapid increase in power generation torque.

  Further, suppression (decrease) and increase of the power generation amount are realized by changing the F duty limit value for setting the upper limit of the excitation duty of the excitation drive transistor 11, and the power generation amount can be easily or surely increased or decreased. Can do. In the power generation control circuit 15 shown in FIG. 2, since the gradual excitation control for gradually decreasing the duty ratio of the PWM signal generated by the PWM circuit 61 is performed, the F duty limit value is the difference between the detected temperature and the predetermined temperature. Even if it rapidly decreases at a change speed corresponding to the deviation amount, the value of the excitation current flowing in the excitation winding 21 gradually decreases.

  Further, since the speed of the count operation of the U / D counter 52 as the speed change amount for suppressing the power generation amount is set to be proportional to the absolute value of the deviation amount that is the difference between the detected temperature and the predetermined temperature, The amount of power generation suppression can be changed according to the degree of temperature rise, and the component temperature of the vehicular generator 1 (the temperature of the rectifier 23, the stator winding 22 and the like) can be quickly lowered.

  FIG. 3 is a diagram illustrating a time change of the F duty limit value when the power generation amount is suppressed. For example, the F duty limit reference value set by the F duty limit reference value setting circuit 56 is set to 100% (full excitation), and the suppression limit value set by the suppression limit value setting circuit 53 is set to 50%. The case has been shown. Further, it is assumed that the detected temperature exceeds the predetermined temperature at time T0 and the deviation amount, which is the difference between them, has turned to a plus. As shown in FIG. 3, when the deviation amount becomes positive at time T0, the F duty limit value (the output value of the subtractor 57) gradually decreases, and the power generation amount is suppressed. The time ΔT (speed change amount for suppressing the power generation amount) until the F duty limit value reaches 50% depends on the count operation speed of the U / D counter 52, that is, the difference between the detected temperature and the predetermined temperature. The F duty limit value decreases more rapidly as the detected temperature is higher, and large power generation suppression is performed.

Embodiment
FIG. 4 is a diagram showing a configuration of a vehicle generator in which the vehicle power generation control device of one embodiment is built, and also shows a connection state between the vehicle generator and a battery or an electric load. . A vehicle generator 1A shown in FIG. 4 is obtained by replacing the vehicle power generation control device 2 included in the vehicle generator 1 of the reference embodiment shown in FIG. 1 with a vehicle power generation control device 2A. The vehicle power generation control device 2A is different from the vehicle power generation control device 2 shown in FIG. 1 in that an excitation current detection excitation circuit 17 and a sense resistor 18 are added instead of the F duty detection circuit. And the point where the power generation control circuit 15 is changed to the power generation control circuit 15A is different. The power generation control circuit 15A performs on / off control of the excitation drive transistor 11, and also sets an adjustment voltage setting value for setting the power generation voltage of the vehicle generator 1A and an excitation current limit for setting an upper limit of the excitation current supplied to the excitation winding 21. By changing the value, power generation amount suppression control based on the temperature detection result by the temperature detection circuit 16 is performed. The sense resistor 18 is inserted between the excitation drive transistor 11 and the E terminal (earth terminal), and generates a terminal voltage proportional to the excitation current flowing through the excitation winding 21. The excitation current detection circuit 17 takes in the terminal voltage of the sense resistor 18 and detects the excitation current flowing through the excitation winding 21.

  FIG. 5 is a diagram showing a detailed configuration of the power generation control circuit 15A. As shown in FIG. 5, the power generation control circuit 15A includes a temperature deviation detection circuit 51, a U / D counter 52, a suppression limit value setting circuit 53, a digital-analog converter (D / A) 54, a selector 55, and an adjustment voltage reference. A value setting circuit 59, voltage comparators 60 and 84, a PWM circuit 61, subtracters 81 and 83, and an excitation current limit reference value setting circuit 82 are provided. In these configurations, components that perform basically the same operations as those of the power generation control circuit 15 illustrated in FIG. 2 are denoted by the same reference numerals, and detailed description thereof is omitted.

  The temperature deviation detecting circuit 51, the U / D counter 52, the suppression limit value setting circuit 53, the digital-analog converter (D / A) 54, and the selector 55 are set to the F duty limit value in the power generation control circuit 15 shown in FIG. Although the basic operation is the same in this embodiment, it is used to output the adjustment voltage set value and the excitation current limit value. In the configuration shown in FIG. 5, a common adjustment voltage setting value and excitation current limit value are output by a set of these configurations, but the adjustment voltage setting value and the excitation current limit value are different. It is sufficient to prepare two sets of these configurations.

  The excitation current limit reference value setting circuit 82 sets the upper limit value of the excitation current flowing through the excitation winding 21 via the excitation drive transistor 11 as the excitation current limit reference value. The subtractor 83 outputs a value obtained by subtracting the output value of the selector 55 (the power generation amount suppression value) from the output value of the excitation current limit reference value setting circuit 82 (excitation current limit reference value) as the excitation current limit value. The voltage comparator 84 is high when the output value of the subtractor 83 is input to the plus input terminal and the output value of the excitation current detection circuit 17 is input to the minus input terminal, and the output value of the subtractor 83 is larger. A level signal is output. Conversely, when the output value of the excitation current detection circuit 17 is larger, a low level signal is output.

  Similarly, the subtracter 81 outputs a value obtained by subtracting the output value of the selector 55 (suppressed value of power generation amount) from the output value of the adjustment voltage reference value setting circuit 59 (adjustment voltage reference value) as the adjustment voltage setting value. The voltage comparator 60 is high when the output value of the subtractor 81 is input to the plus input terminal and the output value of the generated voltage detection circuit 13 is input to the minus input terminal, and the output value of the subtractor 81 is larger. A level signal is output. Conversely, when the output value of the generated voltage detection circuit 13 is larger, a low level signal is output.

  The vehicle power generation control device 1A of the present embodiment has such a configuration, and the operation thereof will be described next. When the temperature detected by the temperature detection circuit 16 exceeds a predetermined temperature, the count value of the U / D counter 52 increases at a speed corresponding to the deviation amount (temperature difference). Therefore, the output value of the digital-analog converter 54 obtained by converting the count value of the U / D counter 52 into a voltage value increases, and the excitation current limit reference value and adjustment voltage output from the excitation current limit reference value setting circuit 82 are increased. The suppression value of the power generation amount subtracted from each of the adjustment voltage reference values output from the reference value setting circuit 59 becomes large. When the state where the detected temperature is higher than the predetermined temperature is maintained, the suppression value of the power generation amount is increased until the suppression limit value set by the suppression limit value setting circuit 53 is reached. Further, the speed until reaching the suppression limit value increases as the deviation amount, which is the difference between the detected temperature and the predetermined temperature, increases. Along with the setting operation of the power generation amount suppression value, the excitation current limit value output from the subtractor 83 and the adjustment voltage set value output from the subtractor 81 are gradually reduced. Since the output of the voltage comparator 84 changes from the high level to the low level when the gradually decreasing excitation current limit value becomes smaller than the excitation current value of the excitation winding 21 detected by the excitation current detection circuit 17, the PWM circuit 61 Regardless of the output voltage level of the voltage comparator 60, the duty ratio of the output PWM signal is reduced. As a result, the excitation current flowing through the excitation winding 21 is reduced, and the amount of power generation is suppressed. On the other hand, when the adjustment voltage setting value that gradually decreases becomes smaller than the generated voltage (the output voltage of the vehicular generator 1) detected by the generated voltage detection circuit 13, the output of the voltage comparator 60 changes from the high level to the low level. Therefore, the PWM circuit 61 decreases the duty ratio of the output PWM signal regardless of the voltage level of the output of the voltage comparator 84. As a result, the excitation current flowing through the excitation winding 21 is reduced, and the amount of power generation is suppressed.

  As described above, in this embodiment, the instantaneous current temperature is controlled by controlling the excitation current limit value or the adjustment voltage setting value so as to decrease the power generation amount at a predetermined change rate when the detected temperature exceeds the predetermined temperature. It is possible to prevent excessive power generation suppression due to the rise. In particular, suppression (decrease) and increase of the power generation amount are realized by varying the exciting current limit value and the adjustment voltage setting value, and the power generation amount can be increased or decreased easily and reliably.

  FIG. 6 is a diagram illustrating a change over time in the adjustment voltage setting value when the power generation amount is suppressed. For example, the adjustment voltage reference value set by the adjustment voltage reference value setting circuit 59 is set to a value corresponding to 14V, and the suppression limit value set by the suppression limit value setting circuit 53 is set to a value corresponding to 4V. The case is shown. Further, it is assumed that the detected temperature exceeds the predetermined temperature at time T0 and the deviation amount, which is the difference between them, has turned to a plus. As shown in FIG. 6, when the deviation amount becomes positive at time T0, the adjustment voltage set value (the output value of the subtractor 81) gradually decreases, and the power generation amount is suppressed. Further, the time ΔT (speed change amount for suppressing the power generation amount) until the adjustment voltage set value reaches 10 V (14V-4V) is the speed of the count operation of the U / D counter 52, that is, the detected temperature and the predetermined temperature. The adjustment voltage set value decreases more rapidly as the detected temperature is higher, and large power generation suppression is performed.

  FIG. 7 is a diagram illustrating a change over time of the excitation current limit value when the power generation amount is suppressed. For example, the excitation current limit reference value set by the excitation current limit reference value setting circuit 82 is set to a value corresponding to 8A, and the suppression limit value set by the suppression limit value setting circuit 53 is also a value corresponding to 8A. The case where it is set to is shown. Further, it is assumed that the detected temperature exceeds the predetermined temperature at time T0 and the deviation amount, which is the difference between them, has turned to a plus. As shown in FIG. 7, when the deviation amount becomes positive at time T0, the excitation current limit value (the output value of the subtractor 83) is gradually reduced, and the power generation amount is suppressed. The time ΔT (speed change amount for suppressing the power generation amount) until the exciting current limit value reaches 0A (8A-8A) is the speed of the count operation of the U / D counter 52, that is, the detected temperature and the predetermined temperature. The excitation current limit value decreases more rapidly as the detected temperature is higher, and large power generation suppression is performed.

In addition, this invention is not limited to the said embodiment, A various deformation | transformation implementation is possible within the range of the summary of this invention. In one embodiment described above, has been inhibited variable to the power generation amount of both of the adjustment voltage setting value and the excitation current limit value may be carried out only one.

  In each of the above-described embodiments, the PWM circuit 61 is used to perform the gradual excitation control for gradually changing the excitation current flowing through the excitation winding 21, but this PWM circuit is used when the gradual excitation control is not performed. 61 may be replaced with a 2-input AND circuit. This AND circuit operates to turn on the excitation drive transistor 11 and cause an excitation current to flow through the excitation winding 21 when both inputs are at a high level.

It is a figure which shows the structure of the generator for vehicles with which the power generation control apparatus for vehicles of reference embodiment was incorporated. It is a figure which shows the detailed structure of a power generation control circuit. It is a figure which shows the time change of F duty limit value in the case of suppressing electric power generation amount. It is a figure which shows the structure of the generator for vehicles with which the power generation control apparatus for vehicles of one Embodiment was incorporated. It is a figure which shows the detailed structure of a power generation control circuit. It is a figure which shows the time change of the adjustment voltage setting value in the case of suppressing electric power generation amount. It is a figure which shows the time change of the exciting current limiting value in the case of suppressing electric power generation amount.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1, 1A Vehicle generator 2, 2A Vehicle power generation control device 3 Battery 4 Electric load 11 Excitation drive transistor 12 Freewheeling diode 13 Power generation voltage detection circuit 14 F duty detection circuit 15, 15A Power generation control circuit 16 Temperature detection circuit 17 Excitation current Detection circuit 18 Sense resistor 51 Temperature deviation detection circuit 52 U / D counter 53 Inhibition limit value setting circuit 54 Digital-analog converter (D / A)
55 selector 56 F duty limit reference value setting circuit 57, 81, 83 subtractor 58, 60, 84 voltage comparator 59 adjustment voltage reference value setting circuit 61 PWM circuit 82 exciting current limit reference value setting circuit

Claims (3)

Temperature detecting means for detecting the temperature of a predetermined measurement location;
When a temperature detected by the temperature detection unit exceeds a predetermined value, a suppression value that is variable at a change rate according to a difference between the temperature detected by the temperature detection unit and the predetermined value is determined. Power generation suppression means for suppressing the power generation amount of the vehicle generator based on the suppression value ;
A switching element for supplying and stopping excitation current to the excitation winding of the vehicle generator;
The power generation suppression means includes the excitation winding so that the power generation voltage does not exceed a value obtained by subtracting the suppression value from an adjustment voltage setting value for setting the power generation voltage of the vehicular generator. The on- off control of the switching element is performed by increasing or decreasing the excitation duty so that the excitation current does not exceed the value obtained by subtracting the suppression value from the excitation current limit value that sets the upper limit of the excitation current to be supplied to A power generation control device for a vehicle characterized by being changed. In claim 1,
The power generation suppression means stops the power generation amount suppression of the vehicular generator when the temperature detected by the temperature detection means drops below the predetermined value after the power generation amount is suppressed, at a predetermined change rate. A power generation control device for a vehicle characterized by increasing a power generation amount. In claim 1,
The power generation suppression means sets the speed change amount for suppressing the power generation amount so as to be proportional to the difference between the temperature detected by the temperature detection means and the predetermined value. apparatus.

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